Lossy video compression standards will lead to noise artifacts. A lossy compression standard compresses a digital video stream by discarding some of the video data. Two possible noise artifacts are ‘mosquito noise’ and blockness.
Mosquito noise manifests itself as ringing or distortions around the edges of items in the image that appear to be shimmering or blurring of dots. The dots resemble mosquitoes swarming around the object, resulting in the naming of the artifact. One current approach involves a one-step de-mosquito process that requires a manual threshold setting to get the correct trade-off between reduction of the artifacts and detail protection. This generally results in less than optimal reduction of mosquito artifacts.
Blockness generally results from the reconstruction of data that has lost even more information. As the pixels for each block are reconstructed, the interior of the block is smooth, but the edges of the blocks do not match the surrounding blocks. One approach uses a filter based de-blocking process to smooth the boundary between blocks. However, filter based de-blocking is not necessarily adaptive enough and may have higher costs than is desirable.
The ability to perform both adaptive and more accurate de-blocking and de-mosquito at a lower cost would be useful.